Here's what to do when you're fed up with your provider, and how to do it.

Isn't complaining pointless?

Whether it's overcharging, bad customer service or problems switching, the energy industry has a bad rep for fixing problems and dealing with complaints.

This can make complaining in the first place seem a waste of time.

But if energy companies are going to improve their reputation they need customer feedback, so it's important to make your voice heard.

According to Charles Breslin, head of customer delivery at small provider Flow Energy, a complaint can be a chance to learn and improve.

"We welcome comments from our customers as they allow us to understand where we need to improve and recognise where we are doing well," he said.

"At Flow we have been able to use feedback from our customers to make improvements to our service and our processes.

"As the energy industry traditionally has a poor reputation when it comes to customer service, we hope that by taking this approach we can use the information we've gathered to promote best practice and make improvements across our business."

Contact your supplier

If your energy company is messing you around, the first thing you should do is get in touch with them.

You might want to go straight to the Energy Ombudsman, but all providers have a dedicated complaints team whose job it is to take you seriously.

There are a few ways you can make contact with your energy provider.

It could be on social media, over the phone or via email, but your supplier will have their own complaint procedure which you can find on their website.

More and more people complain via social media, and it can be effective.

Sending a tweet or posting on a Facebook page will get you noticed quickly and most energy companies will have staff whose job it is to field complaints online.

According to July 2016 research by Gocompare.com, 16 million of us use social media to complain about bad service or products, and companies have paid out £140m in refunds and goodwill gifts in the last 12 months.

First Utility – which was riding high in complaints tables in 2015 – was the first UK company to use Facebook Messenger for customer service.

"We have made it as easy as possible for customers to get in touch in the first instance," said First Utility COO Phil Gripton.

However, you might not be able to resolve your complaint through social media. You may need to email or ring your provider to give them more details, or write a formal letter.

Make sure you take notes of who you speak to and what was said, and get everything in writing – if things go wrong, you'll need evidence later on.

Vote with your feet

"If you're not happy with your energy company's service, one way of telling them is by voting with your feet and switching," said Gocompare.com's energy expert Ben Wilson. You might even save some money in the process.

"Keep in mind that if you're signed up to a tariff and want to switch before it ends you could be asked to pay an exit fee, but the savings you could make by switching might still make it worthwhile."